PROPOSALS THAT EXCEED THE BUDGET OR PROJECT DURATION LISTED ABOVE MAY NOT BE FUNDED.

Summary

Evolution of cancer is complex: from the early lesion to the development of primary tumor to widespread metastasis, numerous and complex interactions occur among normal and malignant cells, as well as their microenvironment. Within the last decade, researchers have found that the tumor environment (TME) is consisted of a multitude of cell types and a host of mediators, whose dynamic interplay contributes to complex tumor behaviors and pose significant therapeutic challenges.

Consisting of non-cancerous cells, TME has an abnormal vasculature, stromal components, immune and non-immune cells embedded in an extracellular matrix (ECM), and plays a critical role in tumor initiation, malignant progression, metastasis and treatment response - barriers to drug delivery and resistance to therapy. There is substantial evidence of a dynamic tripartite interaction between cancer cells, immune cells, and tumor stroma, which contributes to a chronically inflamed TME with pro-tumorigenic immune phenotypes and facilitated tumor metastasis. Both cancer cells and cells in the TME release bioactive molecules (e.g., chemokines, metabolites, and lipid mediators) which can influence cancer progression. Although discovered many years ago via cellular energetics studies (i.e. the Warburg effect) that the metabolic programming and reprogramming of immune cells in TME affects the tumor initiation, the importance of the interconnection of metabolic components and immune signaling pathways for determining the phenotype of tumor-associated macrophage (TAM) was recently noted. In sum, the complex interactions of different cell types (including the immune and non-immune cells), as well as the associated bioactive molecules contribute to the immune-metabolic characteristics of the tumor and its TME.

There are emerging cancer treatment strategies via modulating the immune or metabolic conditions of tumor and its TMEs in recent years with limitations. As an immune-suppressive TME is a barrier to the antitumor function of immune cells, immune priming of TME by radiation has been suggested to promote cancer treatment efficacy. On the other hand, as a sustained inflammation is a common feature of many cancers, novel cancer treatment strategies have been proposed which tackle the inflammation in tumor and TME through the modulation of lipid metabolism and the production of specialized proresolving mediators (SPMs). Immunotherapies utilizing checkpoint inhibitors to modulate the immune components of tumor cells and TME have shown efficacy in treating multiple cancer types, and more are currently undergoing clinical trials; however, immunotherapies only work in a restricted group of patient populations. The less than optimal outcome can be attributed to limited knowledge in individual’s immunological profile encompassing inflammatory cells, immuno-suppressor cells and immunomodulatory factors within the tumor and TME. For this reason, tracking the dynamic evolution of heterogeneous cell populations, molecular characteristics, and metabolic signatures to characterize the immunological status within the tumor and its TME would add significant knowledge in cancer progression and could lead to the development of novel therapeutics and more efficacious treatment strategies.

Studies of immune or metabolic signatures of tissues are usually based on histopathological analysis of the tissue biopsies. However, these methods are destructive and lack temporal information; thus, the ability to use tumor and TME-associated molecular, cellular and metabolic signatures for tumor prediction, diagnosis, prognosis, and therapy response are somewhat limited. The use of techniques capable of in vivo molecular characterization and cell mapping of the tumor and its TME, in its physical location and over time, augmented by the assessment of metabolic signatures, can advance research efforts in this increasingly important topic and could accelerate lead compound identification. Clinical applications of responsive technologies could assist in patient stratification, monitor therapeutic response and modulate therapy accordingly.

Recent advances in imaging techniques are enabling assessment of tumor and TME with improved accuracy due to higher monitoring speed, sensitivity, and resolution. For example, magnetic resonance imaging techniques, with both excellent image resolution and depth penetration, are widely used to detect abnormal pre-malignant, tumor and TME structures and conditions: blood oxygenation level dependent (BOLD)-MRI for hypoxic conditions; Chemical Exchange Saturation Transfer (CEST)-MRI for reduced pH; MR angiography for vascular structure and diffusion MRI for structural integrity; and, MR spectroscopy Imaging (MRSI) for interrogating the concentration of various metabolites. Positron Emission Tomography (PET) of radio-nuclei-labeled tumor or TME-associated molecular and immunological targets has been used in pre-clinical and clinical settings. All these in vivo methods are valuable tools to spatiotemporally examine the targeting efficiency, associated molecular events and provide insight into the normalization of tumor and TME, and its effect on anticancer drug delivery. In parallel, although not applicable in vivo, high throughput analytical tools such as liquid chromatography-mass spectroscopy (LC-MS) and other advanced mass spectrometer techniques allow lipidomic and metabolic analyses in TME’s interstitial fluid and provide functional insights into the activities of tumor and its TME.

Longitudinal evaluation of the immunological status, based on multiple immune or metabolic signatures in the tumor and its TME, within the same subject is a comprehensive strategy for early detection of cancer, the prognosis of tumor progression as well as prediction of treatment outcome. To accelerate research and potentially translational efforts focused on dynamic profiling of the immunological status in tumor and TME, the National Cancer Institute (NCI) requests proposals for the development of tools that can dynamically measure multiple immune or metabolic signatures of the tumor and its TME.

Project Goals

Tumor diagnosis at an early stage is critical to improving survival of patients with the tumor. Similarly, being able to predict tumor response to treatment is essential to eliminate the use of ineffective treatment options and allow alternative treatment options. As such, the ability to characterize the dynamic changes in the immune or metabolic signatures of tumor and TME at the molecular, cellular and metabolic levels in an individual patient for early diagnosis and during treatment is critical. The goal of this solicitation is to develop minimally-invasive, imaging and analytical platforms that can repeatedly evaluate immunological status of the tumor and its TME to facilitate pre-clinical research in the immunological space for better cancer diagnosis and treatment prediction. To be considered for this topic, the proposed technology should be focused on interrogating at least two of the following tumor and TME immunological parameters across time via in vivo imaging techniques which can be augmented by additional in vitro analytical measurements. These parameters should allow comprehensive evaluation of an immunology status, based either on signatures from multiple immune pathways, from both etiological and consequential events, or of both immunogenetic and immunosuppressive natures. Proposals to perform in vivo measurements not meeting the above criteria or to solely develop software tools to analyze multiplexed image data are not responsive to this topic.

Potential molecular, cellular, metabolic and physiological parameters to be measured for characterizing immune or metabolic signatures may include but are not limited to the following:

Novel or currently existing in vivo imaging agents or probes (targeting specific molecular or cellular signatures) may be developed and optimized to enable molecular, cellular and physiological measurements. In vitro assessment of immunosuppressive and immunomodulatory factors and cells, their individual genomic and proteomic profiles, and complex networks promoting tumor growth can be included as a part of the proposal to enhance the specificity of the in vivo tools. Developing software algorithms or tools specifically for the interpretation of multiplexed measurement from the proposal can be included.

Phase I Activities and Deliverables

Phase I activities should generate scientific data to demonstrate proof of concept that the technology can quantitatively characterize immune and/or metabolic signatures with sufficient signal sensitivity and resolution. Expected activities and deliverables should include but not limited to:

Demonstrate robust signal changes in response to in vivo perturbation;

Demonstrate feasibility in generating maps of measurable parameters as a function of time;

If new molecular targets are proposed, demonstrate specific binding/targeting capabilities of the agent/probe to the molecular target (tumor and/or TME target);

If new imaging (or detection) agents are proposed, determine optimal dose and detection window through proof-ofconcept small animal studies with evidence of systemic stability and minimal toxicity;

Benchmark experiments against currently state-of-the-art methodologies;

Present Phase I results to NCI staff.

For successful completion of benchmarking experiments, demonstrate a minimum of 5x improvement against comparable or gold-standard methodologies.

Phase II Activities and Deliverables

Phase II activities should support commercialization of the proposed technology. Expected activities and deliverables may include:

Demonstrate in vivo clearance, tumor accumulation, in vivo stability, bioavailability, and the immunogenicity/toxicity of imaging (or detection) agents or probes;

Demonstrate high reproducibility and accuracy of the imaging agents or probes in multiple relevant animal models;

Demonstrate superiority over currently available imaging or detection tools in spatial and/or temporal resolution;

Demonstrate that sensitivity of proposed imaging agents or probes is sufficient to detect in vivo perturbation;

Demonstrate sensitive maps of measurable parameters as a function of time;

Perform toxicological studies;

Demonstrate utility:

for diagnosis, demonstrate that the probes can detect tumors at early stages and demonstrate superiority to current diagnosis methods;

for predictive/decision, validate the predictive capability of the marker by performing prospective pre-clinical animal trials: stratify the animals into treatment groups and demonstrate that the imaging agent accurately predicts appropriate therapy to use;

for therapy response, demonstrate that the imaging tool can accurately visualize changes in response to therapy and validate characteristics of response and non-response.